This invention relates generally to key making machines and more particularly to an appliance adapted to debur and polish the bow of a freshly cut key.
The cutting of keys on conventional key cutting equipment is an old and well established art. However, it has been a continuous problem in the cutting of such keys that the bow portion of the key which is cut will be unfinished in that it will have burrs or rough edges. If these burrs or rough edges are not removed they can cause the key to fail during use or alternatively can damage the internal parts of the associated locks operated by these keys.
As a result various devices have been developed to overcome this problem such as hand files or for example rotating steel or glass brushes against which the keys can be manually pressed to remove the burrs and to polish the unfinished surfaces of the cut key as is shown in U.S. Pat. No. 3,902,382.
However these prior art devices have problems. Hand filing removes metal and must therefore be carefully utilized to avoid changing the profile of the cut key. The rotating steel or fiber glass brushes wear rapidly and pose a danger to the operator or bystander due to loose bristles or fibers which can be thrown randomly in any direction by reason of the centrifugal forces during the rotation of such brushes.
In a busy key cutting shop these brushes can wear out at the rate of at least one per week.
The present invention covers an improved key deburring and polishing assembly in which a rotatable container is filled with cutting pellets such as Type 100 Nylon Pellets which are rotated in the container at relatively high speed so that when the bow of a key is inserted into the rotating pellets it will be subjected to sufficient forces and bombardment by the pellets to remove burrs and to polish the surface of the key without the extensive removal of metal or change in the finish of the key.